Chinese officials say two shallow earthquakes in rural northwest China have killed at least 73 people and injured hundreds of others.

The U.S. Geological Survey said the first quake, with a magnitude of 5.9, hit at 7:45 a.m. near the city of Dingxi in Gansu province. It struck at a depth of 10 kilometers. A second 5.6 magnitude quake hit the same region about 90 minutes later at a similar depth. The quakes were followed by hundreds of aftershocks.

Officials say several hundred buildings have collapsed and thousands of others have been damaged. Electric power has been lost in much of the region, which is not heavily populated.

Soldiers, police and medical personnel have been sent to the region to search for more victims and help the survivors.